Self-adjusting seal for joints of furnaces



Feb. 7, 1933. E. .1. FRANKLIN SELF ADJUSTING SEAL FOR JOINTS OF FURNACES Filed Jan. 28, 1930 3 Sheets-Sheet l 3g; ATTORNEYS Feb. 7, 1933. E J FRANKUN 1,896,486

5ELF ADJUSTING SEAL FOR- JOINTS 0F FURNACES 4 Filed Jan. 28, 1930 3 Sheets-Sheet 2 lei & WTTTUTHT -WT W WT Lg 1 I Ngfi 0 TN I T\ i I l l 1 I l I I A n n H 1| u H I I n fl 9 i "Y1 n l l "n u "n n n u u la INVENTOR.

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5 Sheets-Sheet 3 E. J. FRANKLIN SELF ADJUSTING SEAL FOR JOINTS OF FURNACES Filed Jan. 28,

Feb. 7, 1933.

INVENTOR fo mrr/ffmfl/f/m I I K ATTORNEYS 2" 9 MW fl/ llll lllllllllHlIIllfllllllIlIll'llllllll Patented Feb. 7, 1933 EDWARD J'. FRANKLIN, OF SALT LAKE CITY, UTAH SELF-ADJUSTING SEAL FOR JOINTS 0F FURNACES Application 'filed January 28, 1930. Serial No. 424,124.

This invention relates to means for sealing the joints of furnaces and the main object of the invention is to provide means for sealing or closing the joints between the parts of the furnace wall which are subject to relative displacement by expansion and contraction due to temperature changes, the invention being particularly directed to the provision of sealing meanswhich will be self-adjusting so as to'maintain tight closure notwithstanding such temperature changes.

A'further object of the invention is to provide an improved, serviceable, flexible, readily applied, refractory sealing means to those parts within or without a furnace structure, between which parts there exists a relative movement due to the expansion or contraction of those or adjacent parts, when influenced by the heating or cooling of such parts 0 when the furnace is being operated.

In the usual types of boiler or other furnaces, there ordinarily exist several pomts at which some metal part of the boiler structure or water wall system is located adjacent to some portion of the materials composing the walls or other closure, surrounding the furnace. Furthermore, there is usually more or less relative movement existing between these parts, due to the inevitable expansion of the several members which comprise the complete boiler and setting structure.

The usual practice in boiler setting construction is to so proportion the dimensional relationship between the several parts that there is a void or free space provided between the parts between which relative expansion is expected. This void, or free space, is customarily filled or packed with a quantity of some fireproof, resilient material, as for 'example, asbestos fiber, such material being tamped into place to the density required to maintain a tight and slightly resilient or yielding seal between the parts in question. This method of providing a resilient seal is not always successful in that the resilient material has a tendency to work out of the space in which it is placed, due to the continual motion of the boundaries of the con- 0 fining space, and also to the fact that the material collects dust, hardens in time and-therefore becomes useless.

In myv invention I propose to substitute any direction, without affectingthe eflicacy of the sealing arrangement. The manner in which this object is accomplished may more readily be seen by reference to the accompanying drawings, and to the detailed de scription applying to each of the same.

The accompanying drawings illustrateembodiments of my invention and referring thereto:

Fig. 1 is a front elevation means. '1 I Fig. 2 is a section online 2+2. in Fig. 1. Fig. 3 is a section'on line 33 inFig. 2. ig. 4 is a section'on line 1-4 in, Fig. 2. Fig. 5 is a vertical section of a portion of a furnace bottom showing of my invention in connection therewith.

Fig. 6 is a vertical section of a furnace boiler showing the application of my invention to the various joints thereof.

Fig. 7 is arsection on line 7 7 in Fig. 6. Fig. 8 is'a vertical section showing the of the sealing the application application of my invention in connection with the seals at the upper and lower ends of a bent watertube wall.

Fig. 9 is a detail View showing the application of my invention to the mud drum.

Referring to Figs. 1 to 4, the seal is composed of a plurality of members 1 mounted endfto end on a suitable support and coop crating with one another and with a supporting means to form a substantially gas tight seal while permitting self-adjustment to compensate for changes in temperature. Each member 1 may be formed as a wing plate of suitable refractory metal or mate- 7 rial adapted to withstand the temperatures existing at that part of the furnace and resting by hinged connection; on supporting or base members 2 which are mounted on a portion 3 of the furnace wall. The supporting members 2 are also preferably formed of a low series of sections of suitable refractory metal or material and the members 1 and 2 are connected by a hinged joint permitting rocking movement of the member 1 on the member 2. For this purpose each member 2 may be provided with an upwardly extending flange or ridge 4 which extends the full length of the base 2 and has a rounded upper edge or bearing 5 on which rests a groove or concave bearing 6 formed on the lower end of the adjacent member 1, the bearings 6 and v5 fitting one another so as to-provide for rocking movement of the member 1 in a vertical plane. At its upper end each wing plate or member 1 rests against a portion f the furnace wall or boiler, the parts being so positioned that the wing plates or membersl are supported in sloping position and the center of gravity of each member 1 is between the bearing 5 and the wall portion 9 and the effect of gravity is such as to cause the seal member 1 to rest against the wall portion 9 and make a substantially gas tight connection therewith.

The members 2 preferably interlock with one another by means of off-sets or projections 10 engaging recesses 11 in the adjacent members so as to more effectively close or seal the oint between adjacent members.

The seal members 1 also overlap one another as shown inFigJl each member 1 being provided with a flange 13 at one end extending over and in contact with a shoulder or rabbett 14; on the adjacent member 1 so as to form a substantially gas tight closure at the joints between adjacent members.

An important application of my invention is in connection with means at the bottom of the'boiler furnace for controlling the admission' of air to the combustion chamber and permitting discharge of ash therefrom, such a construction being desirable where coal dust is used as a fuel. Such a construction isshown in Fig. 5, the members 1 in that case being mounted by hinged connection 6, 5 on a supporting member 2 at each side of a bottom element for the furnace, said bottom element also comprising a central member 15 supporting a refractory furnace bottom element 16 mounted on supporting means comprising side walls 17 each sidewall having vertical flanges 9 against which rest the corresponding seal members 1, the seal members rocking on the hinge bearing 5 and sliding on the vertical means 9 so as to adjust themselves to changes in relative position of the parts 2 and 17 due to temperature changes in the furnace.

In some cases it is desirable to provide the bearing member 9 against which the sloping Wing plate rests, with a ledge or shoulder as indicated at 9 in Fig. '5 so as to shed or deflect ashes from the joint between the members 1 and .9. This is, however, not necessary when the slope of the wing plate is steeper than the angle of repose of the ash.

My improved seal is applicable generally in connection with any of the joints of a boiler furnace where displacement or distortion due to temperature changes is liable to take place. For example, as shown in Figs. 6 and 7, the sealing means can be applied as shown at 10 in connection with the furnace bottom similarly to the construction shown in Fig. 5 and may also be applied as shown at 1?) at the junction between the furnace bottom and the side wall of the furnace, the construction in that case being the same as shownin Figs. 1 to .4. Similarly, the seal may be applied as shown at 10, 1d and 16 at each of the joints between portions of the furnace wall which are subject to displacement. The seal may also be applied as shown at 1] to a joint within the furnace chamber, for example, between deflector plates or wallsQO and 21 mounted on different parts of the boiler construction and subject to relative displacement by reason of changes in temperature. The wing plate 1f may rest on supporting plates 2f which in this case may be clamped to certain of the boiler tubes by suitable fastening means as shown. Said supporting plates may, however, be mounted on a bridge wall or other parts of the furnace.

In case the boiler is provided with Water tube walls as shown at 23 in Figs. 6 and 7, said water tube walls may be made straight as shown, and the sealing means indicated at 1g may be provided between the headers 25 at the lower ends of the water tubes and the side members 26 for the furnace bottom. By this means the expansion and contraction of the water tubes may be provided for without the use of the curved tubes which are generally considered necessary in order to provide for expansion and contraction of Water tube walls. It will be understood that in the constructions above described the various members of tieboiler including the headers and the water tubes are supported on suitable supporting means at the top of the boiler or supported at the bottom or at the mid-height of the tubes in the usual manner and the various parts of the boiler construction so suspendedor supported will be subject to displacement in the operation of the boiler by reason of changes in temperature, and the joints or connections between such parts of the boiler and adjacent wall members of the of the boiler or of the water wall construc- 7 tion.

While my invention may be used with special advantage in connection with the provislon for straight tube water walls, it may also be used to some advantage with water wall constructions comprising curved tubes since it reduces materially the strains which unavoidably occur with such constructions. Such a construction is illustrated in Fig. 8 in which the water wall tubes 28 which are bent at their upper and lower ends to connection with the headers 29 and 30 and are rigidly connected to side wall 31 by clamp means 32 and 33. A sealing member 172., such as above described, is placed between the upper clamp member 32 and a flange member 35 on an upper wall portion 36 and a similar sealing member 1k is placed between the lower clamp member 33 and a support 38 on a lower wall member 37 so as to maintain substantially gas tight closure at the joints between said wall members. The water wall, comprising the tubes 28 and the backing member 31 therefor, may be supported at the upper header, or at the lower header, or at any intermediate point.

Fig. 9 illustratesthe application of my invention to the several closures adjacent to the lower rear drum, commonly denoted as the mud drum, of a vertical bent tube type boiler, such as the well known Stirling boiler. It is a well known andrecognized fact that the actual position of this drum with respect to the boiler setting is continually changing, due to the influence of expansion of the several angularly disposed tubes attached thereto, when the boiler is in service. This relative motion has heretofore rendered very diflicult the construction of satisfactory sealed, resilient joints between the drum and the adj acent furnace walls or other structures. In my invention, referring to'Fig. 9, the mud drum 4:8 is suspended by a series of tubes 49 in the manner usually employed in boilers of this type. Upon theusual refractory bridge wall 50 is mounted the. base piece 2m which supports the wingplate 1m. The wing plate rests at its upper edge against the bearing plate 9m which is attached to the shell of the drum 48, or it may bear directly upon the shell of said drum without the use of the bearing plate 9m. 7

At the rear of the mud drum, there is, in many instances, the need for a dust hopper to collect and dispose of the flue dust and other refuse, which otherwise would accumulate in the back passes of the boiler of the general type being considered. Ordinarily, some type of flexible or resilient junction must be made between the structure of such a dust hopper and the mud drum. Through the use of my invention, I provide such a flexible joint, as illustrated in Fig. 9. The dust hopper 52, which may be of any convenient or suitable shape is partially supported, for example, by the beam member 53, the balance of the supporting members being not shown.-

On the top of the beam member 53 is mount ed the base piece 292 carrying the wing plate 111, which rests at its upper edge against the shell of the drum 48 either directly or through the medium of the bearing plate 9n attached to the shell of the drum.

I claim:

1. A sealing means for closing the oint between two adjacent members of a furnace construction comprising a supporting means mounted on one of said portions and provided with an upwardly extending flange, a plurality of sealing members hingedly mounted on said flange and extending upwardly therefrom and means on the other of said members of the furnace adapted to slidably engage the upper ends of said sealing members to seal the joint between said members while permitting relative movement thereof said supporting means being formed of a plurality of sections provided with overlapping means for sealing the joints between them.

2. Means for sealing the joint between two adjacent parts of a furnace construction comprising a supporting means in connection with one of said parts and havingan upwardly extending flange rounded to form a bearing, a plurality of sealing members having concave bearing portions at their lower ends fitting on said rounded flange so as to permit hinge movement of said movable bearing members on said flange and means on the other said part of the boiler furnace construction adjacent said joint, adapted to engage the upper end portions of said sealing members to form a substantially gas tight connection therewith while permitting hinged movement of the sealing means.

3. A construction as set forth in claim 2 in which the flange d supporting means is formed in a plurality of sections and in which the movable sealing members and the sections of the flange supporting means are provided with overlapping portions for sealing the joints between them.

Intestimony whereof I have hereunto subscribed myname this 9th day of January EDWARD J. FRANKLIN. 

